1. Field of the Invention
The present invention concerns an energy absorbing device with a double winding for motor vehicle steering columns.
The device in accordance with the invention applies in particular to a steering column which can be adjusted in depth or in inclination or a steering column which can be adjusted in depth and in inclination, comprising a steering shaft mounted in a body-tube which is supported and immobilized in the required position, the body-tube being connected by a support assembly to the chassis or to a part of the body of the vehicle.
2. Description of the Prior Art
Ongoing safety improvements concerning steering columns oblige manufacturers to control all parameters of energy absorbing systems. The method of absorbing energy by unwinding a metal wire is increasingly used for steering columns and it is now necessary but difficult to vary the energy absorbing travel in accordance with a defined impact force.
The resulting compromise often leads steering column manufacturers to manufacture wires of complex shape or of varying section. The major disadvantage lies in the use of the product, which leads the manufacturer to costly technology solutions.